“Recently, the Chinese government sent bigger, stronger patrol ships — almost equivalent with naval combatant ships — into the waters around the Senkakus,” Hideaki Kaneda, a retired Japanese vice-admiral, tells The Financial Times. China, which calls the Senkakus the Diaoyus, has competing territorial claims to the islands, and ever since Japan bought them from a private Japanese owner in 2012, Beijing has been more vocal and active in the region. In December, China sent its first armed vessel close to the island chain. According to Tokyo, Beijing is taking advantage of the world’s focus on the South China Sea to be more aggressive in the north.

Earlier this month, Tokyo announced it would send patrols to meet any Chinese ship that sailed too close to the Senkakus. It isn’t clear if they have followed through on this promise or not. Nonetheless, the situation is clearly escalating and Japan lodged several official complaints with Beijing over the recent activity. Japanese Prime Minister Shinzo Abe has been hoping that by not shying away from confrontation with Beijing over its maritime activity, he can keep the Chinese at bay. But if he’s unlikely to back down, so too is his counterpart, President Xi Jinping. This is one game of chicken you can be sure defense officials around the world are watching closely.